s assemble to see how my cannon shoots."

"That's right, Tom. Well, start off, I'm with you."

The two youths labored for some time, being helped, of course, by the
workmen provided by the government, and some from the steel concern.

There were many little details to look after, not the least of which
was the patrolling of the stretch of ocean over which the great
projectiles would soar in reaching the far-off targets at which Tom had
planned to shoot. No ships were to be allowed to cross the thirty-mile
mark while the firing was in progress. So, also, the zone where the
shots were expected to fall was to be cleared.

But at last all seemed in readiness. The gun had been tried again and
again on its carriage. The projectiles were all in readiness, and the
terribly powerful ammunition had been stored below the gun in a
bomb-proof chamber, ready to be hoisted out as needed.

Because the gun had been fired so many times with a charge of powder
heavier than was ordinarily called for, and had stood the strain well,
Tom had no fear of standing reasonably close to it to press the button
of the battery. There would be no retreating to the bombproof this time.

The German officer was occasionally seen about the place where the gun
was mounted, but he appeared to take only an ordinary interest in it.
Tom began to feel more than ever that perhaps his suspicions were
unfounded.

Some officials high in government affairs had arrived at Colon in
anticipation of the test, which, to Tom's delight, had attracted more
attention than he anticipated. At the same time he was a bit nervous.

"Suppose it fails, Ned?" he said.

"Oh, it can't!" cried his chum. "Don't think about such a thing."

Plans had been made for a ship to be stationed near the zone of fire,
to report by wireless the character of each shot, the distance it
traveled, and how near it came to the target. The messages would be
received at a station near the barbette, and at once reported to Tom,
so that he would know how the test was progressing.

"Well, today tells the tale!" exclaimed the young inventor, as he got
up one morning. "How's the weather, Ned?"

"Couldn't be better--clear as a bell, Tom."

"That's good. Well, let's have grub, and then go out and see how my pet
is."

"Oh, I guess nothing could happen, with Koku on guard."

"No, hardly. I'm going to keep him in the ammunition room until after
the test, too. I'm going to take no chances."

"That's